<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>简单易用的倒计时js代码</title>
<style>
*{ margin:0; padding:0; list-style:none;}
body{ font-size:18px; text-align:center;}
.time{ height:30px; padding:200px;}
</style>
</head>
<body>
  <div class="time">
    <span id="t_d">00天</span>
    <span id="t_h">00时</span>
    <span id="t_m">00分</span>
    <span id="t_s">00秒</span>
  </div>
<script>
  function GetRTime(){
    var EndTime= new Date('2017/05/01 00:00:00');
    var NowTime = new Date();
    var t =EndTime.getTime() - NowTime.getTime();
    var d=0;
    var h=0;
    var m=0;
    var s=0;
    if(t>=0){
      d=Math.floor(t/1000/60/60/24);
      h=Math.floor(t/1000/60/60%24);
      m=Math.floor(t/1000/60%60);
      s=Math.floor(t/1000%60);
    }
 
 
    document.getElementById("t_d").innerHTML = d + "天";
    document.getElementById("t_h").innerHTML = h + "时";
    document.getElementById("t_m").innerHTML = m + "分";
    document.getElementById("t_s").innerHTML = s + "秒";
  }
  setInterval(GetRTime,0);
</script>
 
</body>
</html>